As is set forth in the above patents and patent applications, the inventions, including the present one deal with flexible biopsy needle assemblies that allow biopsy tissue samples to be obtained through substantially non-invasive procedures performed on patients by utilizing the flexible needles of these inventions together with an endoscope or bronchoscope. Following insertion of the endoscope or bronchoscope within a body cavity, the flexible biopsy needle assembly is slideably inserted into a passageway provided therefor within the scope. Once positioned adjacent the tumor or the area where tissue is to be sampled, the needle portion of the assembly will be exposed and inserted into the tissue. Insertion of the needle into the tumor can be repeated, by applying force on the proximal end of the apparatus so that through the compressive properties of the apparatus provided by the internal stylet the applied force will be transmitted to the needle. This technique, when used in the bronchia area, has come to be referred to as a transbronchial needle asperation biopsy procedure. Tissue samples can be obtained from directly within the bronchial passageways, the lungs or from tumors located on the body side of these areas. For example, by using this needle assembly one can obtain mediastinum tissue located outside of the bronchial airways. Prior to the development of this technique, such tissues could only be obtained by invasive surgical procedures which are not only more dangerous to a patient but cause various types of suffering and are costly.
In obtaining the tissue sample within the needle it is necessary to apply some negative pressure or suction to the needle once the needle is inserted into the tissue to help assure tissue collection. In my prior needle assemblies, a stylet or guide wire was used internally within the needle assembly to provide sufficient rigidity to thread the needle and catheter assembly through the bronchoscope and during tissue penetration as well as to provide protection for the tip of the needle end to protect the interior lining of the bronchoscope channel. Also, by allowing the guide wire to extend beyond the needle protected the patient from inadvertent needle damage. However, to apply suction to the needle it was necessary to remove the guide wire thereby developing a sufficient suction passage.
It is, of course, time consuming and cumbersome to remove the guide wire and its effectiveness is lost when removed. Accordingly, it would be beneficial to be able to move the guide wire as little as possible, or not at all following tissue penetration. I have also determined that a different needle structure would be more useful with other types of scopes, i.e., endoscopes, or other long tubular structure used within a patient's body, usually a hollow organ, such as the windpipe, lungs, the esophagus, the stomach or intestines. The present design be used in the lungs to obtain lymph node mediastinum which is located outside the windpipe to allow diagnosis of the various diseases as well as to keep track of the staging of lung cancer. It can also be used in the esophagus, stomach and intestine for diagnosis purposes or even therapy, the latter including drainage of cystic lesions like pancreatic cysts thereby eliminating the necessity of a more serious operation and is the only means of which I am aware of for suitably draining pancreatic cysts. The device can also be used in the GI track, not withstanding that the size of the space is larger and that the unique psysiological quality of the GI track, in particular peristalsis activity, would tend to lead a needle away from the biopsy target when such were located outside of the GI track lumen.
Reference is made to the Jamshidi soft-tissue biopsy needle/syringe in which two of four ribs or fins along the plunger are provided with regularly spaced apart saw-tooth indentations that will cooperate with a pair of opposed locking and stop flanges to allow the physician to position the plunger at a predetermined amount of suction as determined by the axial position of the plunger within the syringe. The flanges are provided in a plate fixed to the proximal end of the syringe barrel and the plunger is positioned by twisting the plunger when a pair of the saw-tooth indentations align with the flanges. The plurality of indentations renders the plunger difficult to move axially and is fixed to the syringe.